Appearance Node

The appearance node defines the look of the geometry. This node can
only be defined inside a Shape node.

The fields included in this node are: material, texture,
and textureTransform. All fields are optional but at least one field
should be specified.

The material field contains a
Material node. This node specifies the color of the associated geometry,
see the Shape node, and how the geometry reflects
light. Note that if this field is NULL or unspecified then all lights
defined in the world are ignored when rendering the associated geometry.